The supreme triumph of reason is to cast doubt upon its own validity.
Chemistry ought to be not for chemists alone.
A man does not die of love or his liver or even of old age; he dies of being a man.
Faith which does not doubt is dead faith.
All knowledge has an ultimate goal. Knowledge for the sake of knowledge is, say what you will, nothing but a dismal begging of the question.
To love with the spirit is to pity, and he who pities most loves most.